C# Linq 查找符合条件的记录，如果找到该记录，则返回所有相关记录

Question

我的问题：我正在搜索发生在特定日期的帐户交易。如果我找到当天的交易，那么我需要收集该帐户的交易历史并将其捆绑在一起。我当前的解决方案需要 2 条 linq 语句才能正确恢复数据。但是我还有一些其他的数据库调用，所以我试图减轻负载

我当前的解决方案：首先，我使用 linq 语句收集当天发生的所有交易，并仅返回帐号。然后我重新运行几乎相同的查询，但这次使用我需要的所有内容并使用 where 子句中第一个查询的帐号。我还发现 linq 不喜欢在 where 子句中使用我的匿名类型，因此我在此期间将帐号转换为列表。

我的请求：谁能帮我找到一种更有效的方法来恢复我需要的数据？如果有人可以建议我可以对匿名问题进行更改，我将不胜感激。错误：无法创建“匿名类型”类型的常量值。在此上下文中仅支持原始类型或枚举类型。

我的代码：

public ICollection<ACCOUNT_TRANS> GetTransactionsByDate(DateTime date)

    {

        //Get account transactions that occur on this date

        var results = this.ACCOUNT_TRANS

                          .Select(at => new { at.FK_ACCOUNT, at.COMPLETION_DATE })

                          .Where(at => at.COMPLETION_DATE.Value.Day == date.Day &&

                                        at.COMPLETION_DATE.Value.Month == date.Month &&

                                        at.COMPLETION_DATE.Value.Year == date.Year)

                          .ToList();

        //Extract Account Number and removes the anonymous nature of the data

        var accountNums = results.Select(r => r.FK_ACCOUNT).ToList();

        //Return Transaction history for all changed changed

        var results2 = this.ACCOUNT_TRANS

                           .Include(at => at.ACCOUNT_TABLE1)

                           .Include(at => at.ACCOUNT_TABLE2)

                           .Include(at => at.ACCOUNT_TABLE3)

                           .Include(at => at.ACCOUNT_TABLE4)

                           .Where(at => accountNums.All(r => r == at.FK_ACCOUNT))

                           .ToList();

        return results2;

    }

Answer 1

解决了问题解决了，因为我的头脑因尝试了这么多事情而扭曲。这是代码应该是什么。Linq 想要的样子又好又简单：public ICollection<ACCOUNT_TRANS> GetTransactionsByDate(DateTime date)&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; //Return Transaction history for all changed changed&nbsp; &nbsp; &nbsp; &nbsp; var results = this.ACCOUNT_TRANS&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Include(at => at.ACCOUNT_TABLE1)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Include(at => at.ACCOUNT_TABLE2)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Include(at => at.ACCOUNT_TABLE3)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Include(at => at.ACCOUNT_TABLE4)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Where(at => at.COMPLETION_DATE.Value.Day == date.Day &&&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; at.COMPLETION_DATE.Value.Month == date.Month &&&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; at.COMPLETION_DATE.Value.Year == date.Year)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.ToList();&nbsp; &nbsp; &nbsp; &nbsp; return results;&nbsp; &nbsp; }

Answer 2

试试这个查询，就这个查询。&nbsp; &nbsp; var results2 = this.ACCOUNT_TRANS&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Include(at => at.ACCOUNT_TABLE1)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Include(at => at.ACCOUNT_TABLE2)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Include(at => at.ACCOUNT_TABLE3)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Include(at => at.ACCOUNT_TABLE4)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.Where(at => this.ACCOUNT_TRANS&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; .Where(a => at.COMPLETION_DATE.Value.Day == date.Day &&&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; a.COMPLETION_DATE.Value.Month == date.Month &&&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; a.COMPLETION_DATE.Value.Year == date.Year)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; .Select(a => a.FK_ACCOUNT).Contains(at.FK_ACCOUNT))&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.ToList();